The present invention relates to a disc cartridge for encasing a recording medium such as an optical disc or a magnetic disc.
In general, a magnetic disc or an optical disc is encased in a cassette case made of two shell halves. A hole into which a spindle for rotating the disc is to be inserted is formed in a central portion of the cassette case. Adjacent to the spindle hole, a head insertion hole into which a write and read head is to be inserted is formed in the radial direction to traverse the recording surface of the disc. The head insertion hole is opened and closed by a shutter having an opening corresponding to the head insertion hole.
However, in this disc cartridge, only the head insertion hole is closed by the shutter in a state wherein the spindle hole is exposed to the atmosphere. In this manner, if the spindle hole is exposed to the atmosphere, dust enters inside the cartridge to contaminate the surface of the disc.
Moreover, since an opening of the shutter for opening and closing the spindle hole is simply formed so as to cut a rectangle portion of a planar plate of the cartridge a write and read head cannot be inserted close to the surface of the disc when the head is inserted into the head insertion hole along the surface of the cartridge.
In addition, the shutter is reciprocatingly moved, along a guide portion of the cartridge, by a drive pin provided in a recording and reproducing apparatus (player) and, however, the shutter cannot be smoothly moved because of various defects of the guide portion thereof.